$overrideModelOptions does not apply timezone

[booblin]

I'm thinking is bug

Current behavior:
Changing timezone programmatically (use $overrideModelOptions) dont work

Expected / new behavior:
If we set new timezone, it apply to model

Minimal reproduction of the problem with instructions:

function ChangeModelOptionsDirective () {
  return {
    restrict: 'A',
    require: 'ngModel',
    link: function ($scope, element, attrs, ngModel) {
      ngModel.$overrideModelOptions({
	timezone: '+0400', // dont work
	debounce: {
	  'default': 5000 // it work
        }
     })	     
    }
  };
}

Plunker: http://plnkr.co/edit/7zHR1EKigTMaFjDU1yDc?p=preview

Angular version - 1.6.5

[gkalpak]

You are right, it is a bug (or at least, I believe it is unintended behavior). The reason this happens is that in "date-family" directives, we cache the timezone in the directive's pre-linking phase, which comes before your $overrideModelOptions() call.

I think we shouldn't cache that value (or at least not until later).

In the meantime, you can ensure your call happens before caching the timezone, by moving it in the pre-linking phase and giving your directive a higher-than-default priority:

return {
  priority: 10,
  ...
  link: {
    pre: function ($scope, element, attrs, ngModel) {
      ngModel.$overrideModelOptions({...});
    }
  }
};

[booblin]

Yes, thank.
link pre override options when directive start, but for our business case we need change timezone (offset) in "online".

Now i use this solution

pre: (scope, element, attrs, ngModelCtrl) => {
  ngModelCtrl.$overrideModelOptions({
    timezone: 'utc'
  })
  ngModelCtrl.$parsers.push((value) => {
    let utc = moment.utc(value);
    let serverTimeZone = 'Europe/London'; // for example
    let tzOffsetMinutes = moment.tz(utc, serverTimeZone).utcOffset();
    let serverLocalDate = utc.subtract(tzOffsetMinutes, 'minutes');
    return serverLocalDate.toDate();
  })
}